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Discussion Starter #1
Now that I've had he DEF deleted and the DPF thought I would post my MPG. I'm getting about 18Mpg average, around 600 miles per tank. They say it's a 36 gallon tank but every time I Fill it it the most it takes is 33 gallons, and that's with the fuel light being on for around 30 miles. Has anyone else done the same mods and have what there getting for mpg???
 

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Yeah Id like to know as well... I dont think Im going to void my warranty till it has at least 60k miles on it which isnt too far off. Ive got just over 41k miles right now. The fuel tank is 36 gallons I have put in 35+ gallons a few different times!!! lol Im gettin 16-17mpg average right now stock. So hopefully some are seeing better than 18mpg tuned and deleted
 

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Now that I've had he DEF deleted and the DPF thought I would post my MPG. I'm getting about 18Mpg average, around 600 miles per tank. They say it's a 36 gallon tank but every time I Fill it it the most it takes is 33 gallons, and that's with the fuel light being on for around 30 miles. Has anyone else done the same mods and have what there getting for mpg???
How many miles on the truck?? What kind of driving are you doing while getting the 18 mpg? Highway/City? With or without the Mini Max?
 

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16-17 stock, thats great.. my 08 lmm only gets 14.5 average. Is that mostly city driving?
 

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16-17 stock, thats great.. my 08 lmm only gets 14.5 average. Is that mostly city driving?
Its pretty much 40-60 mix city-highway but with quite a bit of idling. If im doing mainly highway say 75-80% of the time with minimal idling I get around 18. Strictly highway cruising I have seen all the way up to 21 but that only happened twice.
 

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Discussion Starter #8
How many miles on the truck?? What kind of driving are you doing while getting the 18 mpg? Highway/City? With or without the Mini Max?
I have about 14,000 on the truck, I did the delete when It had 2,000 miles. I have a 30 mile commute to work 60% is highway, I have the Mini Max set on mild but i have a lead foot...It's kinda hard no to cause it sounds so sick at WOT!!!


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I dont know what i'm doing wrong then trevor! I get about 16 in the denali with 50k and thats alot of highway driving. And then the worktruck is getting about 14... It's kinda starting to piss me off!
 

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Discussion Starter #10
Yeah Id like to know as well... I dont think Im going to void my warranty till it has at least 60k miles on it which isnt too far off. Ive got just over 41k miles right now. The fuel tank is 36 gallons I have put in 35+ gallons a few different times!!! lol Im gettin 16-17mpg average right now stock. So hopefully some are seeing better than 18mpg tuned and deleted
how long did you run it with the fuel light on to get 35 gallons in it????
 

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Try to avoid running your truck below 1/4 of a tank. Not good on the injection system.
 

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I dont know what i'm doing wrong then trevor! I get about 16 in the denali with 50k and thats alot of highway driving. And then the worktruck is getting about 14... It's kinda starting to piss me off!
Can someone help me?
 

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Can someone help me?
Hmm im not sure. I run synthetic oils. Coast to stops but im not easy off the line so that kinda counteracts eachother. What kinda tire pressure do you run? Id be pissed if I was getting that kinda mileage too
 

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Exactly how?
When you have less than a quarter then there is less pressure on the fuel pump which causes it to work harder to get fuel to the injectors. I know it will cause a fuel pump to go out quicker. Never knew it had an effect on the injectors. I know I always fill up at a quarter. It's such an instinct that I feel like I don't have gas if I'm at a quarter. Haha


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Exactly how?
I knew it was bad on regular cars, because the fuel pump is in the tank. And the fuel is used to cool the fuel pump. But once a diesel fuel pump is primed, I'm not sure the amount of fuel makes a difference on how hard the fuel pump has to work. But also makes sense about the pressure difference. One of those thought experiments. I need a beer, my brain is hurting :drink
 

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Discussion Starter #20
I'm screwed then I always fill up when I'm empty. I have stuck 36.3 gallons in before. My normal is 35 gallons.
I don't understand how you can put that much in!! I always run until the light comes on and then some. The most I have ever put in was 32.8 gallons. Do they all have 36 gallon tanks?


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